An arrhythmia is an abnormal heart rhythm where a patient's heartbeats may be irregular, too slow (bradycardia), or too rapid (tachycardia), and may originate in the atria or ventricles. Atrial tachycardia (AT) and ventricular tachycardia (VT) (collectively referred to as tachycardia) are forms of arrhythmia in which the atria or ventricles contract at a high rate; e.g., 100 or more beats per minute. A tachycardia can be life-threatening because it can lead to fibrillation, in which the heart beats rapidly in a chaotic, purposeless fashion such that the heart cannot pump blood effectively to the body. If untreated, fibrillation can be fatal.
Treatment for tachycardias can include anti-tachycardia pacing (ATP), which attempts to restore a more normal heart rhythm, and is often delivered via an implantable medical device. However, existing ATP techniques may not always be effective since these techniques of delivering ATP are typically unguided and deployed on a trial and error basis. Often, ATP is discontinued after multiple attempts and the implantable medical device is programmed to deliver a defibrillation shock to the heart in an attempt to terminate the tachycardia. However, shock therapy can be painful and can cause damage to the myocardium.
Accordingly, it would be beneficial to provide improved techniques for characterizing a tachycardia and/or selecting treatment for a tachycardia.